Interpretive Summary: In this work, we examined properties and behaviors of previously developed biological thermo-hydrogel in order to further explore its applications and usages. The properties of this novel hydrogel indicated that it possessed much potential in utilizations such as cosmetic products, drug delivery, wound skin care products and tissue engineering. Hydrogels are viscoelastic materials that have many biomedical utilization potentials, such as drug delivery, wound care product, breast implant materials, and tissue engineering etc. Hydrogels can be made from synthetic polymers such as ethylene oxide and vinyl alcohol. There are some biological hydrogels obtained from natural sources such as gelatin, fibrin, collagen, and chitosan. Hydrogels produced from biopolymers and/or natural sources have particular advantages in vivo applications since they are more likely biodegradable, biocompatible, and bioresorbable.

Technical Abstract:
The rheological properties of a newly developed biological thermo-hydrogel made from vegetable oil were investigated. The material named HPSO-VI is a hydrolytic product of polymerized soybean oil (PSO). HPSO-VI exhibited viscoelastic behavior above 2% (wt. %) at room temperature and viscous fluid behavior at 55°C. The function of thermal assembly-disassembly-reassembly for the HPSO-VI hydrogel was completely reversible. The viscoelastic properties of HPSO-VI were strongly dependent on concentration. The analysis of modulus and concentration dependence and stress relaxation measurement indicated that HPSO-VI was a physical gel meaning the cross-linkers between the molecules were physical junctions. HPSO-VI hydrogel also showed fast initial partially recovery of its viscoelastic properties after being subject to a mechanical shear disruption. The function and behavior of the HPSO-VI hydrogel suggest that this biomaterial be a potential candidate for applications in cosmetic products, drug delivery, and wound skin care products.